"Madam Zhao doesn't look like she's from the countryside at all," Madam An began. This banquet was organized by her sister-in-law, and beforehand, she had specially inquired about this Meng Yao, showing that she valued Meng Yao greatly. So, she needed to support her a bit, ensuring that she didn't suffer at the hands of the Grand Princess.
With Madam An breaking this strange atmosphere, others quickly followed suit. They were all sharp-minded individuals. Though the Grand Princess's status was noble, she was, after all, just a princess.
Consort An was the Emperor's most favored and might ultimately ascend to that position.
Seeing how much Consort An regarded Madam Zhao, they'd be fools to belittle her.